Conventionally, a so-called integrated type gas supplying apparatus is used to supply process gas to semiconductor manufacturing equipment, etc.
FIG. 15 shows one example thereof, in which two-way opening and closing valves 41A and 41B, three-way opening and closing valves 42A and 42B, a flow control device 43, etc., are integrated in series via block bodies 44, 45, 46, 47, and 48, each having a gas flow passage, to form one gas supply line, and a plurality of such gas supply lines are disposed and fixed in parallel via block bodies 45 and 49 to constitute an integrated type gas supplying apparatus (Japanese Published Unexamined Patent Application No. Hei 5-172265, etc.).
This type of integrated type gas supplying apparatus provides an excellent effect in that fixing bolts for fixing the respective devices to the block bodies can be removed from the upper side of the apparatus to enable easy replacement of the control devices forming the respective gas supply lines, as well as easy accommodation of addition of gas supply lines, etc.
However, an increase in the number of required gas supply lines inevitably results in an increase in the depth dimension L of the integrated type gas supplying apparatus due to a thermal type flow control device (mass flow controller) or a pressure type flow control device being approximately 20 mm to 24 mm in thickness L0, and this poses a problem of an increase in dimensions of the integrated type gas supplying apparatus.
Also, recently with semiconductor manufacturing equipment, multiple chamber arrangements, provided with a plurality of processing chambers to process a plurality of wafers simultaneously, and chamber multiple process arrangements, with which a plurality of processes are performed continuously in a single processing chamber, are being adopted, giving rise to a need for an integrated type gas supplying apparatus to be provided with multiple gas supply lines to accommodate the increase in the types of supply gases. For example, an integrated type gas supplying apparatus used in semiconductor manufacturing equipment with a 1-chamber multiple process arrangement may be required to have 16 gas supply lines.
However, as the number of gas supply lines increases, the semiconductor manufacturing equipment inevitably becomes large, leading to problems related to an increase in installation space and an increase in the volume of an expensive clean room.
Furthermore, an integrated type gas supplying apparatus is required to switch instantaneously among the various types of process gases to be supplied to a process chamber and supply a specific gas at a predetermined flow rate in a clean state. It is thus essential to reduce the gas flow passage volume in the interior of the integrated type gas supplying apparatus as much as possible, in order to improve the gas replaceability; and to make arrangements to enable easy maintenance and management of the apparatus, in particular, easy replacement and adjustment of the various devices and prevent leakage from connection portions.
However, in actuality, it is difficult to reduce the gas flow passage volume in the interior of the integrated type gas supplying apparatus and, for example, with an integrated type gas supplying apparatus having 16 supply lines, a rated gas flow rate of 1.0 SLM, and a gas flow passage inner diameter of 6.27 mm (¼ inch), it is difficult to reduce the gas flow passage volume in the interior to no more than 120 cc to 150 cc, and, consequently, switching among gas types cannot be performed swiftly, but requires an average time of approximately 5 seconds, thereby giving rise to various problems in terms of productivity and product quality of the semiconductor manufacturing equipment.